2004 年 51 巻 6 号 p. 405-409
The Curie temperature and saturation magnetization of as-deposited Mn, MnZn, NiZn, and Co ferrite thin films by sputtering were different from those of heat-treated films at 700°C-900°C. After heat treatment, Curie temperature and saturation magnetization of Co ferrite thin films were invariable, whereas those of Mn, MnZn, and NiZn ferrite thin films depended on the heat treatment temperature. In the case of the ferrite thin films containing Mn and Zn, these results are explained by a nonequilibrium ion distribution, but another cause must exist in the case of the Co ferrite thin film. As-deposited sputtered ferrite thin films show nonequilibrium phenomena in both Curie temperature and saturation magnetization, whose cause is considered to depend on the ion content.